The present invention relates generally to cassettes for photographic elements, and more particularly, to an x-ray cassette used in computed radiography.
In the field of computed radiography, a photographic element has an image formed thereon by x-rays. The photographic element is subsequently provided to a reader wherein the element is stimulated to emit a radiation pattern that is indicative of the image formed by the x-rays. Typically, storage phosphors are used to capture radiographic images from incident x-rays. Most radiographic procedures are carried out within normal room lighting conditions, accordingly, a primary requirement for any computed radiography x-ray cassette is to shield the storage phosphor from exposure by ambient light.
Cassettes of the kind used in computed radiography may comprise a container having an upper and lower parts that are hinged together so that they can be opened for insertion of a flexible film sheet or a rigid film plate comprising the photographic element. The cassette is closed and latched so that the cassette with the element therein can be used with an x-ray apparatus to produce an image on the photographic element. Then, the cassette is taken to a reader where the cassette is opened and the photographic element extracted by suitable feeders, such as a suction feeding device. The photographic element separates from the cassette, and is transported through the reader where it is stimulated to emit a radiation pattern which is captured for storage and use. The radiation pattern is subsequently erased from the photographic element before being returned to the cassette for re-use.
U.S. Pat. Nos. 5,861,631 (Wendlandt et al.), U.S. Pat. No. 5,869,839(Wendlandt et al.), and 5,943,390 (Wendlandt et al.), commonly assigned and incorporated herein by reference, disclose cassettes of the kind used in computed radiography.
While such cassettes may have achieved certain degrees of success in their particular applications, cassettes are susceptible to various types of damage when dropped or roughly handled. Accordingly, it is desirable to increase the durability of the cassette while minimizing cost and weight, and preserving the same basic nature of design.
Accordingly, a need continues to exist for a cassette which is durable and reduces its susceptibility to damage when dropped or roughly handled, and the same basic nature of design is preserved.
An object of the present invention is to provide a cassette which has increased durability, and is resistant to damage when dropped or roughly handled.
This object is given only by way of illustrative example. Thus, other desirable objectives and advantages inherently achieved by the disclosed invention may occur or become apparent to those skilled in the art. The invention is defined by the appended claims.
According to one aspect of the invention, there is provided a x-ray cassette comprising a shell and a storage phosphor assembly. The shell comprises an upper and lower panel, a first and second side member, and a front end member, with the first and second side members and front end member joining the upper and lower panels to define a cavity having an open end. The storage phosphor assembly comprises an insert plate having a first and second side, a back end member having two ends, and a first and second edge insert. The storage phosphor assembly is adapted to be removably contained within the shell such that the back end member closes off the open end of the shell. The first and second edge inserts are affixed to the first and second sides, respectively. The back end member has at each end an extension extending in a direction parallel to the length of the back end member to interlock the back end member with the first and second edge inserts such that the force of an impact to the cassette is transferred to the back end member rather than to the insert plate to avoid buckling thereof.
The present invention provides a cassette which has increased durability and reduced susceptibility to damage when dropped or roughly handled.